JP2018012329A - Molding unit for container equipped with fluid circuit and pneumatic circuit appearing at top face - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molding unit for a container equipped with a fluid circuit and a pneumatic circuit, having at least one of improvement of compactness, easier use and easier maintenance.SOLUTION: There is provided a molding unit for forming a container with a hollow recess provided toward an inside of the container, containing: a mold having a side wall which defines a cavity having impression of at least a part of the container, appears on a top face of the mold and in which a fluid circuit for heat adjustment of a wall is inserted; and a boxing device. The boxing device includes an insert attached with translating to the side wall, an actuator integrated with the insert and a pneumatic circuit which is for controlling movement of a piston and contains at least one primary duct which appears on a top face of the mold and is for supply to a chamber.SELECTED DRAWING: Figure 1

Description

  The present invention relates to molding containers, especially bottles, jars and canisters, from blanks of thermoplastic material (such as polyethylene terephthalate or PET), and more particularly to molding containers provided with hollow recesses such as incorporated handles. About.

  Container manufacture generally includes a blow molding operation performed in a mold having a wall defining a cavity into which the blank is introduced, the blank being preheated to allow plastic deformation during blow molding. Recall that the wall fits under the influence of the high gas pressure spreading in the blank.

  Some containers are provided with hollow recesses towards the interior of the container and can be made for aesthetic purposes (eg, creating a curve) or for functional purposes (making a handle to grab the container).

  To achieve this, a movable insert is first drawn into the mold wall and deployed in the presence of a container formed in the mold to push the material back when the material arrives. The molding unit provided is in general use and is shown in the internationally filed application WO 2010/063900 (Sidel Participations).

  The technique described in this document, intended for linear molds (with two mold halves mounted in translation relative to each other), makes the boxing device that controls the movement of the insert significantly larger in the radial direction. The wallet mold (where the mold halves are mounted rotationally with respect to each other) cannot be easily reproduced.

  Since actuators are typically pneumatically controlled (ie, using pressurized fluid), the molding unit incorporates a pneumatic circuit to control the actuator and an external connector that ensures the supply of fluid to the pneumatic circuit Must be designed to allow space for joining.

  In addition, the mold cools the container, thus ensuring that the material of the container is cured at the low temperature (usually around 10 ° C.) at the end of the formation or at the end of the molding, ensuring that the material is thermally cured And therefore must be thermally adjusted to be kept at a high temperature (usually on the order of 140 ° C.) in order to be able to increase its mechanical strength.

  Thermal regulation can be ensured by an electrical circuit (when hot). In the most common manner, usually at low temperatures, thermal regulation is ensured by a fluid circuit comprising a passage drilled in the wall of the mold, which is supplied with fluid by an outer tube via a fluid connector. The These connectors are generally connected from the side of the mold as shown in EP 2106898 (Sidel Participations) or equivalent US Pat. No. 8,348,658.

  Actuators and connectors increase the radial bulk of the molding unit and complicate maintenance due to the difficulty of lateral access to the mold despite the use of rapid connectors.

International Publication No. 2010/063900 European Patent No. 2106898 U.S. Pat. No. 8,348,658

One purpose is the next quality,
-Improved compactness,
-Easier use,
-Proposing a forming unit for containers equipped with a fluid circuit and a pneumatic circuit, having at least one of easier maintenance.

For this purpose, make a molding unit for the formation of the container:
-A mold provided with side walls defining a cavity with impressions of part of the container;
A fluid circuit for heat regulation of the wall, comprising a passage drilled in the wall and extending between the supply opening and the discharge opening;
An insert having a front surface with an impression of a local part of the container, movable between a retracted position and a deployed position;
An actuator integrated with the insert to move the insert from its retracted position to its deployed position and vice versa;
A molding unit comprising a pneumatic circuit for controlling the actuator,
The fluid circuit for the thermal regulation of the walls exits on the upper surface of the mold by means of a supply opening and a discharge opening;
A forming unit is proposed, characterized in that the pneumatic circuit for controlling the actuator comprises at least one primary duct which is perforated in the wall of the mold and exits to the upper surface of the mold by the upstream end. The

  In this way, the fluid connection is made by the upper surface of the mold, which can facilitate ease of use, ease of maintenance, and overall miniaturization of the molding unit.

Various additional characteristics may be contemplated alone or in combination. So for example:
The molding unit comprises a fluid connector mounted on the upper surface of the mold, comprising a fluid inlet in communication with the supply opening and a fluid outlet in communication with the discharge opening;
The mold comprises a groove made in the upper surface, extending from an outer end aligned with the discharge opening to an inner end in the vicinity of the supply opening;
The molding unit comprises a pneumatic connector mounted on the upper wall of the mold, comprising a primary inlet communicating with the upstream end of the primary duct;
The pneumatic circuit for controlling the actuator comprises a secondary duct, which is drilled in the mold wall and exits to the upper surface of the mold by the upstream end;
The pneumatic connector includes a secondary inlet in communication with the upstream end of the secondary duct;
The primary inlet of the pneumatic connector is connected to a high pressure fluid source and the secondary inlet is connected to a relatively low pressure fluid source;
The high pressure is greater than 20 bar;
The low pressure is below 12 bar;
The molding unit includes a cover that is attached to the upper surface of the mold and is interposed between the mold and each connector, and is provided with a through hole that allows each connector to communicate with each circuit.

  Other objects and advantages of the present invention will become apparent from the following description of embodiments with reference to the accompanying drawings.

It is a cross-sectional perspective view which shows the shaping | molding unit provided with a pair of boxing apparatus. It is a disassembled cross-sectional perspective view which shows a metal mold | die half body and its related boxing apparatus from an inner side. It is a disassembled sectional view which shows a metal mold | die half body and the boxing apparatus relevant to it from the outside. FIG. 4 is a perspective view and a broken sectional view showing a mold half of FIGS. 2 and 3. FIG. 6 is a horizontal cross-sectional view showing the forming unit cut out in the region of the boxing device. FIG. 5 is a detailed vertical sectional view showing the boxing device in the retracted position of the insert during formation of the container. FIG. 7 is a view similar to FIG. 6 showing the insert in the deployed position. FIG. 6 is a horizontal detailed cross-sectional view showing the boxing device in the retracted position of the insert during formation of the container. FIG. 9 is a view similar to FIG. 8 showing the insert in the deployed position. It is a disassembled perspective view which shows a part of shaping | molding unit. FIG. 3 is a horizontal detailed cross-sectional view showing mold and insert scaling. FIG. 3 is a vertical partial cross-sectional view of a mold showing two opposing inserts in a deployed position. FIG. 3 is a perspective view of a container formed in the molding unit shown in the previous figure. FIG. 14 is a horizontal cross-sectional view of the container of FIG. 13 along the cutting plane XIV-XIV. FIG. 6 is an exploded cross-sectional perspective view showing a mold half and associated boxing device from the inside, according to a modified embodiment. It is a horizontal detailed sectional view which shows the boxing apparatus of FIG. 15 in the expansion | deployment position of insert. It is the perspective view seen from the front of the insert which equips the metal mold | die half body of FIG. 15 and FIG. It is a perspective view from the back surface of the insert of FIG.

  In FIG. 1 shown in a cross-sectional perspective view, a container 2 (such as a bottle or canister as shown in FIG. 13) with a hollow recess 3 provided towards the interior of the container 2 is taken from a blank (usually a preform). There is a molding unit 1 for molding. The container 2 is provided with a main body 4, a bottom portion, and a neck portion 2A that opens on the opposite side of the bottom portion in a standard manner. In the example shown in FIGS. 13 and 14, the hollow recess 3 is a handle formed on the main body 4 of the container so as to be easily grasped.

  In this case, the main body 4 is subdivided into a front part 4A and a rear part 4B in the area of the handle. As shown in FIG. 14, the front portion 4A and the portion 4B have a rounded shape. The rear portion 4B is a portion intended to be held in the palm of the user when the user grasps the container individually.

  The molding unit 1 first comprises a mold 5 provided with a side wall 6 defining a cavity 7 with an impression of a portion of the container 2. In this particular case, the cavity 7 has an impression of the body 4 of the container 2 and the mold 5 further comprises a bottom 8 having an impression of the bottom of the container 2. The mold 5 is made of metal, such as steel or aluminum (this term also includes alloys of aluminum). The cavity 7 (and thus the container 2) extends along a main axis X that defines a vertical direction. All planes perpendicular to the principal axis X are called horizontal.

According to the embodiment shown in the figure, the side wall 6 comprises two mold halves 5A, 5B that respectively define the impression halves 7A, 7B of the body 4 of the container 2, the mold halves 5A, 5B being , Against each other around a common axis formed by hinges,
An open position in which the mold halves 5A, 5B are separated at an angle from each other to allow blank insertion and removal of the formed container 2;
The mold halves 5A, 5B are brought into contact with each other and enclose the mold bottom 8 between them, thereby forming a cavity 7 and defining the impression of the container 2 to be formed (FIGS. 1 and It is mounted rotationally between the closed position (shown in FIG. 5).

  The side wall 6 is provided with a pocket 9 that opens into the cavity 7. As can be seen in particular in FIGS. 6 and 7, this pocket 9 forms a protrusion towards the interior of the cavity 7 and within a protrusion 10 which forms part of the corresponding impression of the hollow recess 3 defining the handle. It is made hollow.

  The embodiment specifically shown in FIGS. 1 and 5 corresponding to a container 2 provided with two hollow recesses 3 which are preferably symmetrical with respect to the overall center plane of symmetry of the container 2 and together form a handle According to the above, each mold half 5A, 5B is provided with a pocket 9 that opens into the impression half 7A, 7B and is hollowed in the protrusion 10 that forms a protrusion toward the inside of the cavity 7. It is done.

  Secondly, the molding unit 1 includes a boxing device 11 for each pocket 9. The term “boxing” is carried out during the formation of the container 2 (more specifically, it is started by pushing the material back locally by a moving part that is initiated during the pre-blow and blow molding phases of the container 2). Shows the molding technology.

  Each boxing device 11 includes a complementary pocket 9 and an insert 12 received therein. Each insert 12 has a front surface 13 having an impression at a local portion of the container 2 (ie a relatively small surface area), more specifically at the bottom of the hollow recess 3. The front surface 13 is intended to push back the material of the container 2 to complete the impression of the hollow recess 3, as will be explained below. The insert 12 is preferably made from aluminum.

  As can be seen in FIGS. 1 and 5, the molding unit 1 is equipped with a pair of (preferably symmetrical) boxing devices 11 in which the inserts 12 are placed facing each other.

  Each insert 12 includes a retracted position (FIGS. 6 and 8) where the insert 12 is at least partially retracted into the pocket 9 and a deployed position where the insert 12 protrudes at least partially into the cavity 7 outside the pocket 9. (FIGS. 7 and 9) between the side wall 6 along the transverse axis T (ie in the example shown, for each mold half 5A, 5B) in a translational manner. .

  More specifically, as clearly seen in FIGS. 6 and 8, in the retracted position of the insert 12, the front surface 13 is included in the pocket 9 and does not exceed the protrusion 10, but in the deployed position of the insert 12, 13 projects into the cavity 7 and extends over the extension of the projection 10, thereby completing the impression of the recess 3 formed hollow in the container 2.

  This configuration is not limiting. Therefore, according to another embodiment, in the retracted position of the insert 12, the front surface 13 of the insert 12 protrudes from the inner edge of the protrusion 10. According to yet another embodiment, in the retracted position of the insert 12, the front surface 13 of the insert 12 is found on an extension of the inner edge of the protrusion 10.

  As can be clearly seen in FIGS. 2 and 3, the insert 12 (as in its pocket 9) has an asymmetric rotational profile about the axis T and prevents rotation of the insert 12 about the axis T. More specifically, the insert 12 preferably has a height (along the overall axis X of the mold 5) that is greater than the width (in the horizontal plane). In the example shown, the insert 12 has an elliptical profile with a long, generally vertical axis.

  As shown in the figure, each boxing device 11 is mounted in and attached to a hollow complementary recess 15 in the side wall 6 (ie, each mold half 5A, 5B in the example shown). An additional sleeve 14 is further provided. The sleeve 14 is preferably made from steel.

  Each boxing device 11 further comprises an actuator 16 that is integral with the insert 12 and moves the insert 12 from its retracted position to its deployed position, or vice versa, the actuator for this purpose being A piston 17 mounted in translation in the sleeve 14 is provided. The actuator 16 is preferably made from aluminum.

  According to the embodiment shown in the figures and more specifically visible in FIGS. 6 to 9, the sleeve 14 is formed on the outer surface 19 of the mold 5 when the sleeve 14 is inserted into its recess 15. And a cylinder 20 projecting transversely from the rear wall 18 and ending with an edge 21.

  The sleeve 14 defines a chamber 22 in which the piston 17 is mounted. Like the insert 12, the sleeve 14 and the recess 15 containing it have an asymmetric rotational profile about the transverse axis T, like the piston 17, thereby preventing any rotation of the piston 17 around it. Thus, the accuracy of the translational guidance of the insert 12 is improved. More specifically, the sleeve 14, its recess 15 and the piston 17 preferably have a height (along the overall axis X of the mold 5) that is greater than the width (in the horizontal plane). In the example shown, the sleeve 14, the recess 15 and the piston 17 have an elliptical profile with a long, generally vertical axis.

  The piston 17 subdivides the chamber 22 into a rear half chamber 22A and a front half chamber 22B. In the example shown, the rear half chamber 22A is restricted on the inside by the piston 17 and on the outside by the rear wall 18 of the sleeve 14. In the example shown, the front half chamber 22 </ b> B is restricted on the outside by the piston 17 and restricted on the inside by the bottom surface of the recess 15.

  The sleeve 14 has a rear groove 23 that opens into the rear half chamber 22 </ b> A by a number of openings (here in the form of through holes) 24 in the sleeve 14 arranged on the periphery thereof, and is provided on the outer peripheral surface of the cylinder 20. Provided on top. In the example shown, the sleeve 14 is provided with two diametrically opposed openings 24 arranged in this particular case along the vertical axis. Alternatively, the sleeve 14 may include more openings 24, eg, four openings 24 disposed 90 degrees (or otherwise) about the transverse axis T.

  The sleeve 14 further has a front groove 25 on the outer peripheral surface of the cylinder 20 which is made in the edge 21 and opens into the front half chamber 22B by several notches 26 arranged around the sleeve 14. Provided. In the example shown, the sleeve 14 is provided with six notches arranged at approximately 60 ° about the transverse axis T.

  A ring 27 attached to the outer surface of the cylinder 20 and compressed between it and the recess 15 ensures the fluid tightness of the grooves 23, 25 to each other and thus of the half chambers 22A, 22B to each other.

  After being introduced into the recess 15, the sleeve 14 is attached to the side wall 6 of the mold 5. As can be seen in the drawings, more specifically in FIGS. 2 and 3, the sleeve 14 is attached to the side wall 6 using at least one bracket 28, which is attached to the mold 5 by means of screws 30. 29 and a tongue-shaped portion 31 that protrudes from the main body 29 and is placed on the rear wall 18 of the sleeve 14 from the outside. In the example shown, the sleeve 14 is attached to the side wall 6 using a pair of brackets 28 mounted vertically on both sides of the sleeve 14.

  Each bracket 28 is advantageously housed in a hollow recess 32 made in a complementary manner in the side wall 6 of the mold 5, so that no protrusions are formed on the outer surface 19 of the mold 5. Thus, the tongue portion 31 is accommodated in a recess 33 formed in the rear wall 18 of the sleeve 14.

  According to the embodiment shown in the figure, the actuator 16 includes a rod 34 extending radially from the piston, on which the insert 12 is fastened, for example by screwing.

  More specifically, in the example shown, the insert 12 is fastened to the rod 34 using a screw 35 that passes through the piston 17 and the rod 34 and is in the rear surface 37 of the insert 12 opposite the front surface 13. The screw hole 36 manufactured in the above is engaged in a spiral manner.

  The insert 12 is advantageously rotationally locked to the actuator 16 by a pin 38 mounted in a hole 39 made in the rod 34, with one protruding end of the pin 38 being a rear surface 37 of the insert 12. In the inside, it accommodates in the hole 40 produced facing.

  As can be clearly seen in FIGS. 6 to 9, the piston 17 is provided with an additional peripheral segment 41 in contact with the cylinder 20, so that in addition to the ring 27, two half chambers 22 </ b> A, 22 </ b> B are provided. Ensure fluid tight partitioning. Segment 41 is advantageously made of a material with a low coefficient of friction, such as bronze, preferably polytetrafluoroethylene (PTFE).

  As can also be seen in FIGS. 6 to 9, the recess 15 is terminated by a partition 42 on the side of the cavity 7, separating the recess 15 from the pocket 9 and defining the front half chamber 22B on the inside.

  A hole 43 is perforated in the partition 42, and the rod 34 of the actuator 16 is preferably inserted into the hole 43 with one or more seal rings 44 </ b> A separating the front half chamber 22 </ b> B from the pocket 9. Is mounted in a translational manner with one or more guide rings 44B interposed. In the example shown, ring 44A is a dynamic lip ring. For ring 44B, this can be made from PTFE (polytetrafluoroethylene).

  Each boxing device 11 includes a fluid circuit 45 for controlling movement of the piston 17 from at least its retracted position to its deployed position. According to an advantageous embodiment, the fluid circuit 45 is pneumatic and the fluid used is a gas under pressure (usually air).

  For this purpose, each circuit 45 is at least one for feeding the chamber 22 (more specifically the rear half chamber 22A), which communicates with the chamber 22 (more specifically the rear half chamber 22A) by the opening 24. One primary fluid duct 46 is provided.

  In practice, as can be seen in particular in FIGS. 1 to 3, 6, 7 and 10, the primary duct 46 is perforated in the mold 5, and the upper end 47 is the upper surface of the mold 5. 48 and opens into the recess 15 in alignment with the rear groove 23 by the downstream end 49 (FIGS. 6 and 7).

  According to the embodiment shown in the figure, the control of the movement of the piston 17 is of the double action type, and each fluid circuit 45 further controls the movement of the corresponding piston 17 from its deployed position to its retracted position. Configured to control.

  For this purpose, each circuit 45 comprises a secondary fluid duct 50 for feeding to the front half chamber 22B, which is in communication with it by a notch 26.

  More particularly, as can be seen in particular in FIG. 4, the secondary duct 50 is perforated in the mold 5, by the upstream end 51, on the upper surface 48 of the mold 5, by the downstream end 52. Alignment with the groove 25 opens into the recess 15.

  According to the embodiment illustrated in the figure, the primary duct 46 is made substantially vertically in the side wall 6 of the mold 5, whereas the secondary duct 50 is slanted in the side wall 6 of the mold 5. (But at a fairly small angle). In FIG. 10, the primary duct 46 and the secondary duct 50 are indicated by thick broken lines.

  As can be seen in FIGS. 1 and 10, the forming unit 1 includes a pneumatic connector 53 for supplying pressurized fluid from at least the primary duct 46. For this purpose, the connector 53 includes a primary inlet 54 that communicates with the upstream end 47 of the primary duct 46. This primary inlet 54 advantageously appears in the form of a duct drilled in the connector 53 and is connected to a primary plug 55 (here male) for connection to a primary pipe (not shown) for supplying pressurized fluid. Open in the mold type).

  The primary inlet 54 is preferably connected via a primary plug 55 and a primary tube to a high pressure fluid source, usually a gas, advantageously above 20 bar (and for example about 40 bar). This can be the source used to blow mold the container, or if desired, another pressure source that produces a different value of pressure than the blow molding source.

  In the example shown, controlling the movement of the piston 17 is a double action and, apart from the primary duct 46, the pneumatic circuit 45 includes a secondary passage 50 for supplying the front half chamber 22B. The pneumatic connector 53 includes a secondary inlet 56 that communicates with the upstream end 51 of the secondary duct 50. This secondary inlet 56 advantageously appears in the form of a duct drilled in the connector 53 and has a secondary plug 57 (for connection to a secondary pipe (not shown) for supplying pressurized fluid). Here also opens in the male type).

  The secondary inlet 56 is connected via a secondary plug 57 and a secondary tube to a fluid source having a relatively low pressure, preferably 12 bar (and for example about 7 bar) or less.

  The upstream ends 47, 51 of the ducts 46, 50 are connected to each other so that they can be commonly connected to their respective sources of pressurized fluid via a single connector 53 mounted on the upper surface 48 of the mold 5. This is advantageously shown in FIG.

  The connector 53 is attached to the mold 5 by snap-on or at least one screw 58, as in the example shown in FIGS.

  According to the advantageous embodiment shown in FIGS. 1 and 10, the molding unit 1 comprises a cover 59 mounted on the upper surface 48 of the mold 5 and interposed between this and the connector 53.

  As can be seen in FIG. 10, the forming unit 1 comprises a fluid circuit 60 (for example hydraulic) for the thermal regulation of the walls 6. The fluid used is advantageously a liquid, for example water or oil. This circuit 60 lowers the temperature of the wall 6 to ensure cooling of the container 2 just formed (usually around 10 ° C.) or ensures the thermosetting of the container 2 and thus thermal In order to increase the degree of crystallinity (and therefore the mechanical strength) by means (usually about 120 ° C.), it is provided to maintain a substantially constant temperature.

  As seen in FIG. 10, the fluid circuit 60 includes a passage 61 drilled in the wall 6 of the mold 5, and a supply opening 62 and a discharge opening 63 made in the upper surface 48 of the mold 5. Extending between. In other words, the fluid circuit 60 exits on the upper surface 48 of the mold 5 through the supply opening 62 and the discharge opening 63.

To facilitate production (by perforation), the passage 61 is subdivided into several sections. In particular:
An upstream section 61A including several holes exiting on the supply opening 62 and made vertically, horizontally and / or diagonally in the wall 6;
Exits on the discharge opening 63, which also includes several holes made vertically, horizontally and / or diagonally in the wall 6 and communicates with the upstream section 61A in the middle zone of the mold 5 Downstream section 61B.

  As can be seen in FIG. 10, which can be seen transparently with a broken line, the passage 61 is perforated around the recess 15 so as not to intersect the ducts 46, 50 of the pneumatic fluid circuit 45.

  As can be seen in FIGS. 1 and 10, after the forming unit 1 has ensured the supply of fresh (or reheated, respectively) liquid to the fluid circuit 60 and has exchanged heat with the wall 6. In order to ensure the discharge of the reheated (or cooled) liquid, a fluid connector 64 mounted on the upper surface 48 of the mold 5 is provided.

  For this purpose, the fluid connector 64 is in communication with the supply opening 62 (here in the form of a duct drilled in the connector 64) and with the discharge opening 63 (again. And a fluid outlet 66 (in the form of a duct drilled in the connector 64).

  In the example shown in FIG. 10, the openings 62 and 63 protrude on the upper surface 48 so as to face each other in a diametrical direction at a certain distance. In order to be able to fluidly connect the openings 62, 63 simultaneously via a compact connector 64, the mold 5 comprises a groove 67 made in the upper surface 48, which groove 67 is connected to the discharge opening 63. It extends from the aligned outer end 68 to the inner end 69 disposed near the supply opening 62.

  According to the preferred embodiment shown in FIGS. 1 and 10, if the molding unit 1 is provided with an additional cover 59 that is attached to the upper surface 48 of the mold 5, this cover 59 is provided between the upper surface 48 and the fluid connector 64. Intervene in between.

  As can be seen from the transparency in FIG. 10, the cover 59 is provided with through holes 70 to 73 for allowing the connectors 53 and 64 to communicate with the respective circuits 45 and 60.

More specifically, the cover 59 is:
A first through hole 70 (oblique) for communicating the primary inlet 54 of the pneumatic connector 53 with the upstream end 47 of the primary duct 46;
A second through hole 71 (vertical) for communicating the secondary inlet 56 of the pneumatic connector 53 with the upstream end 51 of the secondary duct 50;
A third through hole 72 (vertical) for communicating the fluid inlet 65 with the supply opening 62;
A fourth through hole 73 (vertical) for communicating the fluid outlet 66 with the discharge opening 63;
Is provided. In the example shown, the fourth through-hole 73 is open in alignment with the inner end 69 of the groove 67, so that the fourth through-hole 73 is in fluid communication with the discharge opening 63.

  The fluid tightness of the gas and liquid (usually air and water) at the interface between the cover 59 and the top surface 48 is around the upstream ends 47, 51 of the ducts 46, 50 and around the openings 62, 63. (More particularly around the groove 67), for example, secured by an elastomer ring 74 of silicone or natural rubber or synthetic rubber.

  The attachment of the cover 59 to the upper surface 48 of the mold 5 can be ensured by screws 75 in the example shown.

The fact that both the pneumatic circuit 45 and the fluid circuit 60 are on the upper surface 48 of the mold 5 makes it possible to shift the connection for supplying the circuits 45, 60 thereon, thereby at least Three benefits are provided:
Firstly, it is not necessary to accommodate lateral access to the intake (and exhaust) pipe, thereby simplifying the structure of the molding unit 1, in particular the structure of the part supporting the mold 5;
-The radial bulk of the molding unit 1 is then reduced;
Finally, the connection through the upper surface 48 is simpler and easier for the technician in charge of the maintenance of the molding unit 1.

Furthermore, in order to ensure the correct positioning of the insert 12 with respect to the cavity 7 and to further limit the wear of the actuator 16 and the mold 5, each boxing device 11 is advantageously fastened on the actuator 16 on both sides of the piston 17. Provided with a pair of silent blocks 76, 77, ie:
A rear silent block 76 (FIGS. 6 and 8) fastened on the piston 17 by means of screws 78 and sandwiched between the piston 17 and the rear wall 18 in the retracted position of the insert 12;
A front silent block 77 (FIGS. 7 and 9) which is press-fitted into the rod 34 and fastened on the piston 17 by means of a screw 78 and which is sandwiched between the piston 17 and the partition 42 in the deployed position of the insert 12;

  Here, the term “silent block” means (in the singular) HUTCHINSON S. A. French name of the company, from which the generic name used to indicate a flexible mounting device or a device for shock absorption between two elements (see eg Lausse Dictionary "dictionairere Larousse") Note that the use of “silent block” or “silent block (s)” in this application refers to such devices.

  According to a preferred embodiment, each silent block 76, 77 is preferably made of a polyurethane grade polyurethane marketed under the name Zurcon Z20® by the Trereburg Company. This material exhibits the dual advantage of enhanced hardness (which promotes positioning accuracy of the insert 12) and good wear resistance, thereby promoting the reliability and durability of the boxing device 11.

  The mounting of each boxing device 11 on each mold half 5A, 5B is illustrated in FIGS.

  The silent blocks 76 and 77 are fastened to the actuator 16 by screws 78. The pin 38 is press-fitted into the hole 39 and the end of the rod 34 protrudes by a screw 35 for fastening the insert 12 introduced into the actuator 16. Next, the piston 17 is inserted into the sleeve 14, and then the sleeve equipped with the seal ring 27 is introduced from the outside of the mold 5 into the recess 15 along the transverse axis T, and the rod 34 is It is inserted into the hole 43.

  The sleeve 14 is attached to the side wall 6 of the mold by a bracket 28, and the bracket 28 is mounted in each recess 32 and screwed to the side wall 6. The insert 12 is inserted from the inside of the mold halves 5A, 5B into the pocket 9 along the transverse axis T until it contacts the end of the rod 34, and the pin 38 is inserted into the rear surface 37 of the insert 12. It is accommodated in the hole 40 produced in the inside.

  The insert 12 is then fastened onto the rod 34 by means of a screw 35, and the tightening in its screw hole 36 is an opening made along the axis T in the rear wall 18 of the screw driver or sleeve 14. Secured by a suitable wrench (depending on the impression formed on the screw head) that passes through part 79.

  When the fastening of the insert 12 onto the actuator 16 is completed, the opening 79 is closed in a fluid-tight manner by press-fitting or screwing the plug 80 as shown in FIGS.

  FIGS. 11, 12 and 14 show the scaling of the part of the molding unit 1 which makes it possible to form a hollow recess 3 in the container 2.

In this framework, the following is noted:
A. Cumulative chord length measured in a horizontal plane including the transverse axis T of the protrusion 10 and the protrusion formed by the insert 12 in the deployed position;
B. The chord length measured in a horizontal plane including the transverse axis T of the protrusion formed by the insert 12 in the deployed position, beyond the protrusion 10;
C. The measured width of the insert 12 horizontally (ie perpendicular to the main axis X);
D. Chord length measured in a horizontal plane including the axis T of the protrusion 10 at the retracted position of the insert 12;
E. Maximum transverse extension (measured along axis T) of the protrusion formed by the insert 12 beyond the protrusion 10;
F. Maximum cumulative transverse extension (measured along axis T) of the protrusion formed beyond the protrusion 10 by the protrusion 10 and the insert 12 in the deployed position;
F '. Maximum transverse extension (measured along axis T) of protrusion 10 only;
G. Width measured in the transverse direction of the rear part 4B of the body 4 (the width G is considered to be equal on the container 2 or on the impression in the mold 5);
H. Travel distance of the insert 12 (or piston 17) measured in mm between the retracted position (dashed line in FIG. 11) and the deployed position (solid line in FIG. 11);
I. Offset measured in the horizontal plane on the container 2 between the axis X (considered in the container 2) and the bottom of the hollow recess 3: in the mold 5, I was measured in the horizontal plane , Approximately corresponding to the offset between the axis X (which is considered to be in the mold 5) and the transverse axis T.

  Extensions E, F and F ′ are “maximum” if the recess 3 and the protrusion 10 and the insert 12 do not show symmetry with respect to a vertical plane including the transverse axis T, as shown in FIG. be called. This is why, as FIG. 11 shows, the extensions E and F are measured from the side of the insert 12 (or the side of the protrusion 10) that maximizes that value.

  As already seen, the protrusion 10 forms part of the opposing impression of the hollow recess 3 in the container 2. In the retracted position of the insert 12, the transverse extension F ′ of only the protrusion 10 is such that a gap remains between the opposite protrusions 10, measured in the transverse direction, indicated by K, and its width is blown During molding, it is sufficient to allow the preform in which the container 2 is formed to pass during expansion. This width K is usually about 40 mm.

  As a result, the travel distance H of the insert 12 and thus the radial bulk of the boxing device 11 can be limited, and the compactness of the molding unit 1 can be promoted.

  In practice, the travel distance H of the insert 12 from its retracted position to its deployed position is small, that is, 20 mm or less. Furthermore, this travel distance is advantageously greater than or equal to 10 mm. The travel distance H of the insert 12 is usually about 15 mm.

  The cumulative transverse extension F of the protrusion 10 and the insert 12 in the deployed position is such that, in the deployed position of the two inserts 12, there is a void between them so that each hollow recess 3 is recessed. In other words, as shown in FIG. 14, the handle formed in the container 2 back to back by the two hollow recesses 3 does not penetrate. The width measured in the transverse direction of the gap between the opposing inserts 12 in the deployed position is denoted J. This width J is usually on the order of 15 mm, which corresponds to the distance between the two hollow recesses 3 that together form the handle of the container 2.

Extensions E and F are such that E is 85% or less of F:
E ≦ 0.85 ・ F

  Although limited, the protrusion formed beyond the protrusion 10 by the insert 12 in the deployed position allows the recess 3 to be deepened despite the small travel distance H.

Furthermore, the recess 3 must be deep enough to facilitate grasping of the container 2. For this purpose, the transverse extension E is advantageously more than 30% of the cumulative transverse extension F.
E ≧ 0.3 ・ F

More specifically, the transverse extension E is preferably 35 mm or less.
E ≦ 35mm

On the other hand, this transverse extension E is preferably 10 mm or more:
E ≧ 10mm

In addition, the transverse extension E is preferably less than 45 mm, minus the value of the offset I:
E ≦ 45mm-I

  Similarly, it is advantageous to limit the chord length B of the protrusion formed by the insert 12 in the deployed position as a function of the cumulative chord length A of the protrusion formed by the protrusion 10 and the insert 12.

Therefore, B is preferably no more than 80% of A:
B ≦ 0.8 ・ A

  In this way, the amount of material stretched by boxing remains limited on the vertical extension (along axis X).

Further, B is preferably at least 35% of A:
B ≧ 0.35 ・ A

  Eventually, this allows the material to stretch sufficiently, but does not stretch it to the point where it adversely affects its visual appearance (the overstretching phenomenon results in a whitish discoloration of the material).

  It is also possible to enlarge or reduce the insert 12 by connecting the chord length B of the insert 12 to the width C thereof.

Therefore, the relationship between chord length B and width C is advantageously 2.3 or less:
B ≦ 2.3 ・ C

On the other hand, this relationship is advantageously greater than 1.3:
B ≧ 1.3 ・ C

  It is also possible to scale the insert 12 by connecting the chord length B to its transverse extension E.

Thus, the relationship between the chord length B of the protrusion formed by the insert 12 in the deployed position and its transverse extension E is preferably not more than 3.5:
B ≦ 3.5 ・ E

In contrast, this relationship is advantageously greater than or equal to 2.2:
B ≧ 2.2 · E

More specifically, the chord length B of the protrusion formed by the insert 12 in the deployed position is preferably 75 mm or less:
B ≦ 75mm

In contrast, the chord length B of the protrusion formed by the insert 12 in the deployed position is preferably 50 mm or more:
B ≧ 50mm

  It may be advantageous to connect the cumulative chord length A to the cumulative transverse extension F.

More specifically, the relationship between cumulative chord length A and cumulative transverse extension F is preferably 3.3 or less:
A ≦ 3.3 ・ F

In contrast, this relationship is advantageously 2 or more:
A ≧ 2 ・ F

In the table below, examples of parameter A to J value ranges (in millimeters) are given.

  The procedure for forming the container 2 is as follows.

  The first step is to introduce a blank preheated to a temperature higher than the glass transition temperature of the material into the mold 5 in the open position (usually for PET with a glass transition temperature of about 80 degrees). The blank is heated to a temperature of about 120 degrees). Each insert 12 is in its retracted position.

  The mold 5 is then closed and a fluid under pressure (especially air) (eg about 7 to 15 bar) is injected into the blank, while at the same time the blank is preferably stretched by a sliding rod. Under pressure, the blank material is brought into the vicinity of the side wall 6 and the mold bottom 8, but is not firmly applied there. As shown in FIGS. 6 and 8, under pressure, the material can expand slightly in the pocket 9, possibly partially applied to the front surface 13 of the insert 12.

  Each insert 12 is then moved toward its deployed position. For this purpose, pressurized fluid (here high pressure air of 20 bar or higher, usually around 40 bar) is injected into the rear half chamber 22A via the primary duct 46 and the rear groove 23, while the front At the same time, the fluid present in the part half chamber 22B is discharged through the secondary duct 50 via the front groove 25. Under the pressure differential between the rear half chamber 22A and the front half chamber 22B, the piston 17 together with the insert 12 with which it is integrated, in the direction of the cavity 7 in the transverse direction, is divided by a front silent block 77. The partition 42 thus determines the end point of travel of the insert 12 in the deployed position.

  The insert 12 pushes the material back (but without puncturing it) until it reaches its deployed position like a plunger, and the handle is then formed hollow in the body 4 of the container 2 (see FIG. 7 and FIG. 9).

  At the same time that the insert 12 is moved towards the deployed position, the pressure in the container 2 is increased (usually to a value between about 20 and 40 bar) and the container 2 in contact with the side wall 6 and the mold bottom 8 Impression acquisition is improved. Since the side wall 6 and the mold bottom 8 are thermally regulated, cooling of the container 2 (or heating in the case of thermosetting) is promoted and mechanical rigidity is promoted by maintaining the adhesion of the material to them. To do.

  After a time delay (for a sufficient number of seconds), the container is decompressed, the mold 5 is opened, and the container 2 is removed from the mold 5.

  The insert 12 is returned to its retracted position before or after the opening of the mold 5. For this purpose, pressurized fluid is injected into the front half chamber 22B via the secondary duct 50 and the front groove 25, while the fluid present in the rear half chamber 22A simultaneously with the rear groove 23. Through the primary duct 46. Under the pressure difference between the front half chamber 22B and the rear half chamber 22A, the piston 17 is moved transversely toward the outside of the mold 6 along with the insert 12 with which it is integrated. It is moved until it hits the rear wall 18, which determines the end of the progression of the insert 12 in the retracted position.

  Compared to a normal boxing device in which the piston 17 is mounted directly in a recess made in the mold 5, the presence of the additional sleeve 14 functioning as a wear part limits the wear of the side wall 6 of the mold 5 (and And the reliability of the molding unit 1 is improved.

  Furthermore, the assembly of the fluid circuit 45 in the mold 5, more specifically the production of the supply ducts 46, 50 in the side wall 6 of the mold 5 by means of a connection made on the upper surface 48, Limiting the transverse bulk promotes the overall compactness of the forming unit 1.

  The separation of the recess 15 from the pocket 9 by the partition 42 and the mounting of the insert 12 from the inside of the mold half 5A (or 5B) makes it possible to achieve a good fluid tightness of the half chambers 22A, 22B. , Promoting the effectiveness of the boxing device 11 and thus improving the quality of the container 2.

  The asymmetric shape (here elliptical) of the insert 12 and the sleeve 14 prevents the insert 12 from rotating and promotes good impression acquisition of the hollow recess 3. The preferential uniform distribution of the openings 24 (and notches 26) makes it possible to ensure a good distribution of pressure in the rear half chamber 22A (or in the front half chamber 22B) and guide the insert 12 And the acquisition of a good impression of the hollow recess 3 is promoted.

  Variations of the molding unit 1 are shown in FIGS. 15 to 18.

  This variant includes all the characteristics of the molding unit 1 described above, except for the following additional or modified characteristics.

  First, the insert 12 is provided with at least one passage 81 extending from a rear end 82 that opens into the pocket 9 to a front end 83 that opens onto the front surface 13.

  According to the first embodiment, the (or each) passage 81 may be perforated around the insert 12 in the form of a tunnel (or groove). According to the preferred embodiment shown in FIGS. 15-18, the (or each) passage 81 is drilled into the body of the insert 12.

  In this case, its (or each) passage 81 opens on the rear surface 37 of the insert 12 as can be clearly seen in FIG.

  According to the embodiment shown in FIGS. 17 and 18, the insert comprises a plurality of passages 81. These passages 81 are advantageously distributed around the rod 34 when fastened on the insert 12. In the example shown, it can be seen that if the insert 12 is provided with a counterbore 84 into which the rod 34 is fitted, the passages 81 are distributed around the counterbore 84.

  Second, the front half chamber 22B is in fluid communication with the pocket 9.

  For this purpose, the rod 34 is grooved, i.e. it is provided with a groove 85 made in its outer surface parallel to its axis (parallel to the axis T).

  These grooves 85 facilitate fluid communication between the front half chamber 22B and the pocket 9.

These configurations allow the circulation of the fluid (air if the fluid used is air) by the front half chamber 22B, the groove 85, the pocket 9, and the passage (or passages) 81. And fluid circulation
-Facilitate cooling (or heat regulation) of the insert 12,
Facilitate the cooling of the material of the container 2 and its separation from the front face 13 of the insert 12 when the insert 12 is withdrawn.

  This fluid circulation is achieved during the injection of fluid into the front half chamber 22B, which controls the retraction movement of the piston 17 (and thus the insert 12): a portion of the injected fluid passes into the pocket 9 via the groove 85. Leakage is introduced into the passage (plural passages) 81 by the rear end 82 and exits on the front face 13 by the front end 83 as indicated by the arrow in the detailed inset of FIG.

  By restricting the heating of the insert 12, the side wall 6 of the mold 5 is cooled, while at the same time, an increase in the insert temperature exceeding the glass transition temperature (Tg) of the thermoplastic material constituting the container is avoided, On the other hand, expansion of the insert 12 which prevents proper sliding into the pocket 9 is avoided. The sheet of air created between the front face 13 of the insert 12 and the container 2 makes it possible to maintain the shape of the hollow recess 3 formed in the container 2 by the insert 12 in the deployed position.

  More specifically, the injection of low pressure fluid into the front half chamber 22B (and hence the pocket 9) is achieved before the injection of high pressure fluid into the rear half chamber 22A stops. Thus, fluid circulation on the front surface 13 of the insert 12 begins before its retraction. As a result, air circulates between the blown container 2 and the insert 12 to ensure its cooling.

  Thereafter, the pressure in the container 2 is released, and then the pressure in the rear half chamber 22A is also released. Since the pressure in the front half chamber 22B is maintained, the insert 12 is moved from its deployed position toward the retracted position, and then the pressure in the front half chamber 22B is released.

  This structural design and the operating method described above makes it possible to simplify the structure of the mold, since the pressure duct of the front half chamber 22B is used to ensure the cooling of the insert 12, This prevents relying on dedicated equipment (eg, specific ducts for supplying coolant). In addition, since the container 2 is used to create a wall effect for guiding the sheet-like distributed air flow that moves to lick the front face 13, this provides a good effect of cooling. Therefore, the temperature of the insert 12 can always be kept lower than the glass transition temperature of the material of the container 2.

DESCRIPTION OF SYMBOLS 1 Molding unit 2 Container 2A Neck part 3 Hollow recessed part 4 Main body 4A Front part 4B Rear part 5 Mold 5A, 5B Mold half 6 Side wall 7 Cavity 7A, 7B Impression 8 Mold bottom part 9 Pocket 10 Protrusion part 11 Boxing apparatus 12 Insert 13 Front surface 14 Sleeve 15 Complementary recess 16 Actuator 17 Piston 18 Rear wall 19 Outer surface 20 Cylinder 21 Edge 22 Chamber 22A Rear half chamber 22B Front half chamber 23 Rear groove 24 Opening 25 Front groove 26 Notch 27 Seal ring 28 Bracket 29 Main body 30 Screw 31 Tongue part 32 Hollow recessed part 33 Recessed part 34 Rod 35 Screw 36 Screw hole 37 Rear face 38 Pin 39 Hole 40 Hole 41 Peripheral segment 42 Partition 43 Hole 44A Seal ring 44B Guide ring 45 Empty Fluid circuit 46 Primary fluid duct 47 Upstream end 48 Upper surface 49 Downstream end 50 Secondary fluid duct 51 Upstream end 52 Downstream end 53 Pneumatic connector 54 Primary inlet 55 Primary plug 56 Secondary inlet 57 Secondary plug 58 Screw 59 Cover 60 Fluid circuit 61 Passage 61A Upstream section 61B Downstream section 62 Supply opening 63 Discharge opening 64 Fluid connector 65 Fluid inlet 66 Fluid outlet 67 Groove 68 Outer end 69 Inner end 70 First through hole 71 Second through hole Hole 72 Third through-hole 73 Fourth through-hole 74 Elastomer ring 75 Screw 76 Rear silent block 77 Front silent block 78 Screw 79 Opening 80 Plug 81 Passage 82 Rear end 83 Front end 85 Groove A Accumulated string length B Chord length C Width of insert measured horizontally D In Chord length measured in the horizontal plane of the Sart E Maximum transverse extension F Maximum cumulative transverse extension F 'Maximum transverse extension G Width measured in the transverse direction at the rear of the body H Travel distance I Offset T Transverse axis X Main axis

Claims (10)

In the forming unit (1) for forming the container (2),
A mold (5) provided with a side wall (6) defining a cavity (7) having a partial impression of the container (2);
A fluid circuit (60) for heat regulation of the wall (6) comprising a passage drilled in the wall and extending between the supply opening (62) and the discharge opening (63) A fluid circuit (60) of;
An insert (12) having a front face (13) having an impression of a local part of the container (2), movable between a retracted position and a deployed position;
An actuator (16) integral with the insert (12) to move the insert from its retracted position to its deployed position and vice versa;
A molding unit comprising a pneumatic circuit (45) for controlling the actuator (16),
A fluid circuit (60) for thermal regulation of the wall (6) exits to the upper surface (48) of the mold by means of a supply opening (62) and a discharge opening (63),
A pneumatic circuit for control is drilled in the wall (6) of the mold (5) and exits to the upper surface (48) of the mold (5) by the upstream end (47) (at least one primary duct ( 46), the molding unit (1).   A fluid connector (64) mounted on the upper surface (48) of the mold (5), the fluid inlet (65) communicating with the supply opening (62) and the fluid outlet communicating with the discharge opening (63) The forming unit (1) according to claim 1, characterized in that it comprises a fluid connector (64) comprising (66).   The mold (5) is a groove (67) made in the upper surface (48), from the outer end (68) aligned with the discharge opening (63), in the vicinity of the supply opening (62). Molding unit (1) according to claim 2, characterized in that it comprises a groove extending to the inner end (69).   A pneumatic connector (53) mounted on the upper wall (48) of the mold (5), comprising a primary inlet (54) in communication with the upstream end (47) of the primary duct (46). The forming unit (1) according to any one of claims 1 to 3, characterized in that it comprises a pressure connector.   A pneumatic circuit (45) for controlling the actuator (16) is drilled in the wall (6) of the mold (5) and is on the upper surface (48) of the mold (5) by the upstream end (51). 5. The forming unit (1) according to any one of claims 1 to 4, characterized in that it comprises a secondary duct (50) exiting at.   Molding according to claims 4 and 5, characterized in that the pneumatic connector (53) comprises a secondary inlet (56) in communication with the upstream end (51) of the secondary duct (50). Unit (1).   The primary inlet (54) of the pneumatic connector (53) is connected to a high pressure fluid source and the secondary inlet (56) is connected to a relatively low pressure fluid source. The molding unit (1) described in 1.   8. Molding unit (1) according to claim 7, characterized in that the high pressure is greater than 20 bar.   9. Molding unit (1) according to claim 7 or 8, characterized in that the low pressure is 12 bar or less.   A cover (59) mounted on the upper surface (48) of the mold (5) and interposed between the mold (5) and each connector (53, 64), each connector (53, 64) 10. The cover (59) according to any one of claims 4 to 9, characterized in that it comprises a cover (59) provided with through holes (70, 71, 72, 73) communicating with the circuit (45, 60). Molding unit (1).

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